Keke Xiaoa and Yan Zhoub open this book by examining the effectiveness of combined ultrasonic-acid pre-treatment for the improving of sludge dewaterability, the role of Fe (II) oxone conditioning on sludge dewaterability, and the applications of different treatments. Next, María Isabel González-Bravo, Ph.D. and Eva Lahuerta-Otero, Ph.D. explore the correlation between future environmental risk perception and sustainable development in European countries. The authors discuss cultural factors and social attitudes on eco-innovation. Afterwards, Keke Xiaoa and Yan Zhoub discuss methods of sludge treatment while discussing recent developments. Keke Xiaoa and Yan Zhoub go on to discuss anaerobic digestion for sludge treatment in the following chapter, supplementing this. Subsequently, Paul J. Oberholster, Petri F. Oberholster, Christoff Truter, and Anna-Maria Botha present a study that examines the link between river phosphorus sensitivity, self-purification capacity, and benthic algae biomass downstream from waste water treatment plants in the middle Olifants River sub catchment in South Africa. Then, Huynh Viet Khai presents a study on organic vegetables and customer willingness to pay for them in the Vietnamese Mekong Delta. Huynh Viet Khai also presents a study based in the Vietnamese Mekong Delta in the following chapter, focusing on rice farmers and their attitudes towards pesticides. Ending the book, Marco Costa and Magda Monteiro suggest the use of change point detection methods in a hydrological basin in Portugal.